/* Copyright 2013-2015 www.snakerflow.com.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.snaker.engine.helper;

/**
 * 断言帮助类
 * 
 * @author yuqs
 * @since 1.0
 */
public abstract class AssertHelper {
    /**
     * 断言表达式为true
     * 
     * @param expression
     * @param message
     *            异常打印信息
     */
    public static void isTrue(boolean expression, String message) {
        if (!expression) {
            throw new IllegalArgumentException(message);
        }
    }

    /**
     * 断言表达式为true
     * 
     * @param expression
     */
    public static void isTrue(boolean expression) {
        isTrue(expression, "[Assertion failed] - this expression must be true");
    }

    /**
     * 断言给定的object对象为空
     * 
     * @param object
     * @param message
     *            异常打印信息
     */
    public static void isNull(Object object, String message) {
        if (object != null) {
            throw new IllegalArgumentException(message);
        }
    }

    /**
     * 断言给定的object对象为空
     * 
     * @param object
     */
    public static void isNull(Object object) {
        isNull(object, "[Assertion failed] - the object argument must be null");
    }

    /**
     * 断言给定的object对象为非空
     * 
     * @param object
     * @param message
     *            异常打印信息
     */
    public static void notNull(Object object, String message) {
        if (object == null) {
            throw new IllegalArgumentException(message);
        }
    }

    /**
     * 断言给定的object对象为非空
     * 
     * @param object
     */
    public static void notNull(Object object) {
        notNull(object, "[Assertion failed] - this argument is required; it must not be null");
    }

    /**
     * 断言给定的字符串为非空
     * 
     * @param str
     */
    public static void notEmpty(String str) {
        notEmpty(str, "[Assertion failed] - this argument is required; it must not be null or empty");
    }

    /**
     * 断言给定的字符串为非空
     * 
     * @param str
     * @param message
     */
    public static void notEmpty(String str, String message) {
        if (str == null || str.length() == 0) {
            throw new IllegalArgumentException(message);
        }
    }
}
